Fuel pumps dying

[Sambino]

Morning all.

My 1988 (E) 325i cabby is not well at the mo.

Not sure what's causing this issue but I'm now on my third fuel pump since ownership ( 1.5 years) granted one was second hand and other two brand new.

Any help most appreciated on what the possible cause of premature death of these pumps.

Thanks

[pianist]

Fuel pumps good brand? Fuel filter changed? Any rust in tank that could block it? Fuel pressure should be checked when fited incase fpr is over pressurising ( but that would cause running issues).
Anything I've missed?

[Sambino]

I changed fpr and pumps genuine -,no rust and I think I changed filter - need to double check

[Brianmoooore]

Mechanical failure or electrical failure? There's two halves to a pump, and both are known to fail.

[Sambino]

All I know 3 pumps have died on me so wonder if car is the cause? Electrical ?

[Brianmoooore]

There's no known electrical fault that can cause a pump to fail (that wouldn't make itself extremely obvious as regards the rest of the car.)
The only thing I can think of that would kill the mechanical side is if there was abrasive grit in the tank that was getting into the pump. There would have to be a considerable amount of grit, since the pick up area for the pump is continuously washed clean by the returning, filtered fuel from the engine.

[Sambino]

Thank you Brian. Is there any mileage in me taking the tank off And cleaning out? Or will I need a new tank? Also I don't think I have changed my fuel filter.

[minesapint]

Why are you not taking apart the pumps which have failed to find the reasons for their failure?

[Sambino]

Because they are new- working on the assumption that they shouldn't fail in a short space of time a˜•
Plus I am not that tech minded to know what I'm doing with regards to these pumps.

[Sambino]

Found a few bits from boys in US who think rust in tank - maybe drain off? Or buy new tank altogether?

[pianist]

To add to this, all this rust might be cloging fuel lines and filter which adds more strain on the pump and might be overheating it. You need to investigate this more closely

[Sambino]

Just looked at the tank on the left side - it's got a deep dent! Like palm size and good depth.

I may just change the tank as it may be causing problems transferring fuel around the tank

[Sambino]

Update!

Looked into tank and there's a separate area where the pump sits - almost like a bowel. At the bottom there is what I can describe as rust sediment. It's not much at all but I'm guessing this could be the cause. Seem strange but it's only a few particles.

Nonetheless I am going to bite the bulliet and get new tank. Anyone know of best price?? These aren't cheap. Saw one one on eBay!- £150

While I was under the car had the pleasure to see a dripping exhaust just before rear silencer a˜aa˜aa˜a new exhaust too.

The joys of owning an e30 a˜±

[Brianmoooore]

What condition is the pump pick up filter in?

[Sambino]

It looked fine ! But I have been given a new replacement as I have 12 mths warranty

[Sambino]

Although the my spare cheapo from eBay had a bit of spotted grain but nothing that would make you think it would block it!

[Sambino]

Hi Guys.

I am a very close to removing the tank everything is off but I'm stuggling to get the propshaft off. The bolts are so tight and rusted. It's quite tight in there too. How can I get them off??

Also there was more sediment when I pumped the petrol into a bucket.

Fuel filter was chucking up black bits too.

Please advise if I should get new tank or clean and change filter ?

Many thanks

[Sambino]

Oh and will the lines need cleaning too?

[bosers]

I changed the tank on mine, was a real ball ache. However, if you've got rust and shoite in the tank, its the only way forward. Good luck with getting it sorted.

[Sambino]

Cheers Bosersa‘aaaa did you manage the prop ok?

[bosers]

Yeah it just unbolts, the tank fixings were hardest part as they were rusted up.

[Brianmoooore]

Prop nuts aren't usually seriously rusted, but you do need a good quality combination spanner, usually with an unofficial extension on it.